A light emitting device using light emitting elements is small, provides good power efficiency, and emits light of bright color. Further, the light emitting elements are semiconductor elements, and therefore there is no concern for blowout. The light emitting elements have characteristics of good initial driving performance and are robust against vibration and repetition of on and off of lighting. The light emitting elements have these good characteristics, and therefore light emitting devices using light emitting elements such as light emitting diodes (LEDs) and laser diodes (LDs) are utilized as various light sources.
FIG. 14 is a perspective view illustrating a method for manufacturing a conventional light emitting device. FIG. 15 is a perspective view illustrating an intermediate of the conventional light emitting device. FIG. 16 is a perspective view illustrating the conventional light emitting device.
Conventionally, as a method for manufacturing a light emitting device, a method is disclosed for insert-molding a lead frame with a non-translucent, light reflecting white resin, and molding a resin-molded body which has concave cups at predetermined intervals through the lead frame (e.g., refer to Patent Document 1). Although quality of a material of a white resin is not clearly described, as is insertion-molding performed and as is clear from the figures, a general thermoplastic resin is used. As a general thermoplastic resin, for example, a thermoplastic resin such as liquid crystal polymer, PPS (polyphenylene sulfide), and nylon is often used as a light blocking resin-molded body (e.g., refer to Patent Document 2).
However, the thermoplastic resin has little adhesion with a lead frame, and the resin part and lead frame are likely to be detached. Further, the thermosetting resin has lower resin fluidity of the resin and therefore is not adequate to mold a resin-molded body of a complicated shape, and has little light resistance. In recent years in particular, the output of a light emitting element is remarkably improved and, as the output of a light emitting element is increased, light deterioration of a package made of a thermoplastic resin becomes more distinct.
In order to solve the above problems, a light emitting device using a thermosetting resin for a material of a resin-molded body is disclosed (e.g., refer to Patent Document 3). FIG. 17 is a perspective view and sectional view illustrating a conventional light emitting device. FIG. 18 is a schematic sectional view illustrating a method for manufacturing the conventional light emitting device. It is disclosed that, with this light emitting device, metal wires are formed from a metal foil by a common method such as punching or etching and are further arranged in a mold of a predetermined shape, and a thermosetting resin is filled in a mold resin inlet to transfer-mold.
However, this manufacturing method has difficulty in manufacturing multiple light emitting devices in a short time. Further, there is a problem that a great amount of a resin of a runner part is discarded per one light emitting device.
As a different light emitting device and manufacturing method therefor, an optical semiconductor element mounting package substrate which has a light reflecting thermosetting resin composition layer on the wiring substrate, and manufacturing method therefor are disclosed (e.g., refer to Patent Document 4). FIG. 19 is a schematic view illustrating steps of manufacturing a conventional light emitting device. This optical semiconductor element mounting package substrate is manufactured as an optical semiconductor element mounting package substrate of a matrix pattern which has a plurality of concave parts, by attaching a printed-wiring board having a flat plate shape to a mold, filling a light reflecting thermosetting resin composition in the mold, and heating and pressuring molding the light reflecting thermosetting resin by means of a transfer-molding machine. Further, it is also disclosed that a lead frame is used instead of a printed-wiring board.
However, these wiring board and lead frame have a flat plate shape and have a small adhering area because a thermosetting resin composition is arranged on this flat shape, and therefore there is a problem that, for example, a lead frame and thermosetting resin composition are likely to be detached upon singulation.
Patent Document 1: Japanese Patent Application Laid-Open No. 2007-35794 (paragraph [0033] in particular)
Patent Document 2: Japanese Patent Application Laid-Open No. 11-087780
Patent Document 3: Japanese Patent Application Laid-Open No. 2006-140207 (paragraph [0028] in particular)
Patent Document 4: Japanese Patent Application Laid-Open No. 2007-235085